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A160624
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Denominator of Laguerre(n, 2).
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4
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1, 1, 1, 3, 3, 15, 45, 315, 315, 2835, 14175, 155925, 467775, 6081075, 42567525, 638512875, 58046625, 10854718875, 8881133625, 1856156927625, 9280784638125, 194896477400625, 2143861251406875, 3792985290950625, 147926426347074375
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OFFSET
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0,4
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LINKS
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FORMULA
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Denominators of coefficients in expansion of exp(-2*x/(1 - x))/(1 - x). - Ilya Gutkovskiy, Aug 29 2018
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EXAMPLE
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1, -1, -1, -1/3, 1/3, 11/15, 37/45, 209/315, 113/315, 23/2835, -4381/14175, -84389/155925, -310517/467775, ... = A160623/A160624.
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MAPLE
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seq(denom(orthopoly[L](n, 2)), n=0 .. 100); # Robert Israel, Jul 23 2015
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MATHEMATICA
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PROG
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(PARI) for(n=0, 30, print1(denominator(sum(k=0, n, binomial(n, k)*((-2)^k/k!))), ", ")) \\ G. C. Greubel, May 06 2018
(PARI) a(n) = denominator(pollaguerre(n, 0, 2)); \\ Michel Marcus, Feb 05 2021
(Magma) [Denominator((&+[Binomial(n, k)*((-2)^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // G. C. Greubel, May 06 2018
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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